Today: 7 p.m. at Qualcomm Stadium. On the air: Ch. 8, NFL Network

EXHIBITION Seahawks at Chargers

For the Chargers’ new head coach, the devil (and the Lombardi Trophy) is in the details.

“The more you can prepare people, the better you’re going to be,” said McCoy, whose Chargers open their preseason schedule today at home against the Seattle Seahawks. “When everyone understands what to do, how to do it, you’ve got a better chance to be successful.”

And so three-quarters of the way through what would be a 12-minute post-practice talk on Wednesday afternoon, McCoy ran through what Saturdays would be like during the season.

And he demands a higher level of neatness in the locker room.

And he knows what, why and how virtually everyone in football operations is carrying out particular tasks.

And he makes sure the folks in the family tent have an unobstructed view of practice.

And he stops a two-minute drill to address a specific scenario that may or may not happen.

“If I could pick one thing that stands out,” said quarterback Philip Rivers, now playing for this third head coach in 10 NFL seasons, “it is that he has a plan for everything.”

So far, McCoy is preaching to a congregation of believers, though you can’t help but imagine some players flashing back to interminable college lectures during Wednesday’s on-field address.

Said center Nick Hardwick of what has most impressed him about McCoy: “The attention to detail and how he coaches us through situations and coaches us very thoroughly.”

Well, tonight against the Seahawks at Qualcomm Stadium comes the next deliberate step. It is McCoy’s first game, albeit a practice one, as an NFL head coach.

Details are what a coaching staff’s functioning on game day is about. Success often comes down to decisions made under pressure, and handling stress is best done when prepared, and sweating the small things is crucial to avoiding big problems.

So while McCoy says it is “just another game,” he also knows it is when he and his staff will truly get to put some highly detailed operations into practice.

How they communicate between the coaches’ booth and sideline, communicate about injuries, make adjustments on the fly, handle replay challenges — all things to be tested.

To this point, there is a lot to like in all the details and reason to be hopeful about the change at Chargers Park.

For one thing, McCoy has made it clear in no uncertain terms that it is important how players treat each other, their families and fans.

Fact is, that’s not a concept entirely foreign to those who played under previous coach Norv Turner. But the new coach has a new way of saying it, and there are reasons for the players to hear it differently.

“You have to be open-minded to it,” safety Eric Weddle said. “You can’t just figure what we’ve been doing and the things that individually and collectively what we’re doing has been successful. It hasn’t. We haven’t made the playoffs. It hasn’t been good enough. So changes have been made, and you’re either on board with it or you’re not going to be here … That’s been one of the biggest things in a sense — that there hasn’t been one guy saying, ‘This is stupid. What they’re doing is dumb.’ Not one. When you have that, you’re going to have a lot of great plays. And everyone will go in the right direction.